US 11,914,763 B1
System and method for conformal head worn display (HWD) headtracker alignment
Christopher M. Boggs, Gainesville, VA (US); Gavin P. Haentjens, Arlington, VA (US); William T. Kirchner, Ashburn, VA (US); Brandon E. Wilson, Portland, OR (US); and Kurt I. Jaeger, Catlett, VA (US)
Assigned to Rockwell Collins, Inc., Cedar Rapids, IA (US)
Filed by Rockwell Collins, Inc., Cedar Rapids, IA (US)
Filed on Sep. 26, 2022, as Appl. No. 17/953,227.
Int. Cl. G09G 5/00 (2006.01); G06F 3/01 (2006.01); G06T 7/73 (2017.01); B64D 47/08 (2006.01); G06T 19/20 (2011.01)
CPC G06F 3/012 (2013.01) [B64D 47/08 (2013.01); G06T 7/73 (2017.01); G06T 19/20 (2013.01); G06T 2207/30204 (2013.01); G06T 2219/2004 (2013.01)] 14 Claims
OG exemplary drawing
 
1. An aircraft-based head worn display (HWD) system, comprising:
an aircraft positioning system configured to determine one or more of:
a position and orientation (pose) of an aircraft relative to a navigational reference frame;
an absolute position of the aircraft in an earth-centered reference frame;
and
a pose of the aircraft relative to a platform reference frame;
a display unit associated with a display reference frame, the display unit configured to present display imagery to a wearer of the HWD;
an optical-inertial headtracker configured for estimating a headtracker pose of a first optical reference frame with respect to a second optical reference frame;
the HWD system associated with an alignment mode wherein the HWD system is configured to:
define one or more far-field features proximate to the aircraft, each far-field feature corresponding to a three-dimensional (3D) position relative to the navigational reference frame;
determine, via the aircraft positioning system, at least one feature pointing vector associated with each far-field feature, each feature pointing vector relative to the platform reference frame;
estimate a nominal head pose for aligning the display reference frame to the platform reference frame, the nominal head pose configured to position the one or more far-field features within the display unit field of view (FOV);
render, via the display unit, the one or more far-field features based on the at least one feature pointing vector and the nominal head pose;
based on an alignment of the one or more rendered far-field features to their corresponding 3D positions, determine a latched headtracker pose;
determine an updated headtracker alignment based on the nominal head pose, the latched headtracker pose, and an extrinsic calibration of the display unit relative to the first or second optical reference frame;
update, based on the updated headtracker alignment, a display alignment for aligning the at least one feature pointing vector to the display reference frame.